The present invention relates to a new and improved apparatus for the continuous wet treatment of strand-like or rope-like textile material, wherein treatment liquid flows through a pipe system in countercurrent with respect to the direction of movement of the continuously conveyed textile material, and the textile material is squeezed at least once within the pipe system.
With heretofore known methods of this type and equipment for the performance of such methods, for instance as disclosed in Swiss Pat. No. 385,152 or Austrian Pat. No. 202,959, the increased exchange or interaction, which is strived for by the counterflow principle, between the treatment liquid adhering to the textile material and the remaining liquid located in the pipe system, decreases with increasing velocity or speed of movement of the textile material and constant velocity of the treatment liquid. This is so because with increasing velocity there is entrained, by the textile material, a corresponding greater amount of treatment liquid in the same direction of flow.
This undesired effect, as has likewise already been proposed, could be at least partially counteracted by providing relatively larger cross-sectional areas of the pipe or conduit system. Yet, this solution requires an appreciably greater quantity of treatment bath. This, in turn, is contrary to the more recent attempts which are being made, in consideration of the increasingly more stringent requirements regarding protection of the environment, to maintain the liquid consumption as small as possible and to optimumly utilize the treatment agent or liquid.
Also, it is already known to the art, as for instance documented by the previously mentioned patents, to improve the action of a treatment liquid at a textile material by squeezing such textile material once or a number of times during the course of its treatment. The squeezing action is accomplished, for instance, by passing the textile material between squeezing or pinch rolls or guiding such in a zig-zag configuration over deflection rolls which then simultaneously produce a squeezing action at the textile material.
Particularly when using narrow pipe or conduit systems, as such is desired for the purpose of saving on treatment liquid, there is however formed, forwardly of the squeezing location or locations, a slug of treatment liquid, since the squeezed-off treatment liquid tends to collect or dam-up and partially or completely occupies the cross-section of the pipe conduit or the like. Consequently, there is not only impaired a treatment in countercurrent flow within such dam-up or collecting region, rather such damming-up of the treatment liquid also hinders the throughflow of the treatment liquid from one end to the other end of the pipe system.